Arjo Nimbus 4 User manual

Nimbus 4
Nimbus Professional
649933EN_09 • 05/2022
INSTRUCTIONS FOR USE

Design Policy and Copyright
® and ™ are trademarks belonging to the Arjo group of companies.
© Arjo 2022.
As our policy is one of continuous improvement, we reserve the right to modify designs without
prior notice.The content of this publication may not be copied either whole or in part without the
consent of Arjo.
WARNING
To avoid injury, always read this Instructions for Use and accompanied documents
before using the product.
Mandatory to read the Instructions for Use

Contents
General Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
About this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Intended use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
About Nimbus 4 and Nimbus Professional . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Nimbus Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Nimbus 4 Mattress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Mattress CPR and Transport Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Nimbus Professional Mattress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Clinical Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Contraindications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Cautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Care of the patient when sitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Preparing the System for Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Installing the Mattress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Installing the Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Testing the Power Fail Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Connecting the Tubeset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Disconnecting the Tubeset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
System Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Controls, Alarms and Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Pump Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Pump Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Installing the System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Inflating the Mattress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Comfort Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Shut Down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Mattress Vent Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Guidelines for Selecting Mattress Vent Valves to Open . . . . . . . . . . . . . . . . . . . .15
Transport Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Deflating the Mattress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
CPR Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Nimbus Professional Mattress: Patient Positioning Guide . . . . . . . . . . . . . . . . .18
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Supine Position (face up) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Prone Position (face down) - Not for Homecare Environment . . . . . . . . . . . . . . .20

Decontamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Routine Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Nimbus 4 and Nimbus Professional Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Nimbus Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Nimbus 4 and Nimbus Professional Mattresses . . . . . . . . . . . . . . . . . . . . . . . . . .23
Serial Number Labels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Troubleshooting and Alarm Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Technical Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Electromagnetic Compatibility (EMC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30

(iii)
General Safety
Before you connect the system pump to a mains socket, read carefully all the installation instructions
contained within this manual.
The system has been designed to comply with regulatory safety standards including:
• EN60601-1:2006/A1:2013 and IEC 60601-1-1:2005/A1:2012.
• EN60601-1-11:2010; IEC 60601-1-1-11:2010 and IEC60601-1-8:2012.
• ANSI/AAMI ES 60601-1(2005)+AMD(2012) and CAN/CSA-C22.2 No.60601-1(2008)+ (2014).
Safety Warnings
• It is the responsibility of the caregiver1to ensure that the user can use this product safely.
• Whilst the patient is unattended, the decision to use safety sides should be based on clinical
assessment and in line with local policy.
• Alignment of the bed frame, safety sides and the mattress should leave no gap wide enough to
entrap a patient's head or body, or to allow egress to occur in a hazardous manner where
entanglement with the mains power cable and tubeset or air hoses may result. Care should be
exercised to prevent occurrence of gaps by compression or movement of the mattress. Death or
serious injury may occur.
• Make sure that the mains power cable and tubeset or air hoses are positioned to avoid causing a
trip or other hazard, and are clear of moving bed mechanisms or other possible entrapment
areas. The mains power cable of this pump is designed to allow movement of the bed, and
should be fitted into the cable management flaps along the sides of the mattress, as described in
this manual.
• Electrical equipment may be hazardous if misused. There are no user-serviceable parts inside
the pump. The pump's case must only be removed by authorised technical personnel. No
modification of this equipment is allowed.
• The mains power socket/plug must be accessible at all times. To disconnect the pump
completely from the electricity supply, remove the plug from the mains power socket.
• The CPR control and/or the CPR indicator tag must be visible and accessible at all times.
• Disconnect the pump from the mains power socket before cleaning and inspecting.
• Keep the pump away from sources of liquids and do not immerse in water.
• Do not use the pump in the presence of uncontained flammable liquids or gasses.
• The cover of this product is vapour permeable but not air permeable and may present a
suffocation risk.
• Do not use the mattress without a cover, it provides a protective barrier.
• Bags supplied with this equipment may present a suffocation risk; to avoid the risk of
suffocation keep the bags away from babies and small children.
• When not fitted to a bed, the bed hooks on the pump may present a hazard to small children.
Store the pump in a safe place.
• Only the pump and mattress or seat combination as indicated by Arjo should be used. The
correct function of the product cannot be guaranteed if incorrect pump and mattress or seat
combinations are used.
• If a serious incident occurs in relation to this medical device, affecting the user, or the patient
then the user or patient should report the serious incident to the medical device manufacturer or
the distributor. In the European Union, the user should also report the serious incident to the
Competent Authority in the member state where they are located.
1. Caregiver may be a healthcare professional or a lay person who operates this medical device.

(iv)
Precautions
For your own safety and the safety of the equipment, always take the following precautions:
• Placing extra layers between the patient and the mattress potentially reduces the benefits provided by
the mattress and should be avoided or kept to a minimum. As part of sensible pressure area care, it is
advisable to avoid wearing clothing which may cause areas of localised high pressure due to creases,
seams, etc. Creases in the top cover and placing objects in pockets should be avoided for the same
reason.
• Do not expose the system, especially the mattress, to naked flames, such as cigarettes, etc.
• In the event of a fire, a leak in the seat or mattress could propagate the fire.
• Do not use or store the system in direct sunlight.
• Do not use phenol-based solutions to clean the system.
• Make sure the system is clean and dry prior to use or storage.
• Never use sharp objects or electrically heated under blankets on or under the system.
• Store the pump and mattress in the protective bags supplied.
• Pets and children must be supervised in the vicinity of the system.
• Always make sure the drag handles are fastened to the base cover, when the patient is NOT being
transported.
• When the pump is in use the operator should remain in the area in case the system alarms.
Electromagnetic Compatibility (EMC)
This product complies with the requirements of applicable EMC Standards. Medical electrical equipment
needs special precautions regarding EMC and needs to be installed in accordance with the following
instructions:
• The use of accessories not specified by the manufacturer may result in increased emissions by, or
decreased immunity of, the equipment, affecting its performance.
• Portable and mobile radio frequency (RF) communications equipment (e.g. mobile/cell phones) can
affect medical electrical equipment.
• If this equipment needs to be used adjacent to other electrical equipment, normal operation must be
checked before use.
• For detailed EMC information contact Arjo service personnel.
Expected Service Life
The Nimbus®pump has an expected service life of seven years. To maintain the condition of the pump, have
the pump serviced regularly according to the schedule recommended by Arjo.
Do NOT use unapproved accessories or attempt to modify, disassemble or otherwise misuse the Nimbus 4
and Nimbus Professional system. Failure to observe this caution could result in injury, or in extreme cases,
death.
End of Life Disposal
• Fabric material used on the mattresses or any other textiles, polymers or plastic materials etc. should be
sorted as combustible waste.
• Mattresses at the end of life should be disposed of as waste according to the national or local
requirements which may be landfill or combustion.
• Pump units have electrical and electronic components should be disassembled and recycled per Waste
of Electrical and Electronic Equipment (WEEE) or in accordance with local or national regulation.

1
1. Introduction
About this Manual This manual is your introduction to the Nimbus 4 and Nimbus
Professional systems. You must read and fully understand this
manual before using the system.
Use this manual to initially set up the system, and keep it as a
reference for day-to-day routines and as a guide to maintenance.
If you have any difficulties in setting-up or using the Nimbus 4 and
Nimbus Professional systems, contact your local Arjo sales office,
listed at the end of this manual.
Intended use The intended use of this product is to prevent and/or manage
pressure ulcers for patients up to 250 kg (550 lb).
The Nimbus 4 and Nimbus Professional systems should be used
as part of a prescribed plan of care (refer to “Indications” on
page 5).
About Nimbus 4 and
Nimbus Professional
Nimbus 4and Nimbus Professional are highly effective Dynamic
Flotation Systems providing active therapy for the prevention and
management of pressure ulcers.
The systems consist of a pump and mattress replacement. The
support system can be used on hospital beds and domestic beds
in acute care, long-term care and homecare environments,
including private homes. Beds with divided sections for
independent elevation of a patient's head and/or knees can be
adjusted with these mattresses in position.
Both systems use the same Nimbus pump, which has two
operating modes:
• Dynamic mode that cycles the support surface beneath the
patient every 10 minutes providing periods of pressure relief for
the whole body.
• Static mode where the support surface remains constant (all
cells equally inflated).
WARNING
To avoid injury to the patient when operating the
Nimbus 4 and Nimbus Professional system as a
caregiver and as a lay person:
• Make sure the system is operating according to
section “Operation” on page 13“.
• If the system is not operating correctly, see
section “Troubleshooting and Alarm
Conditions” on page 24“.
• If the system is still not operating correctly, or if
you have concerns, contact the patient’s doctor
or nursing staff for advice.

2
The Nimbus Professional mattress combines all the qualities of the
Nimbus range of mattresses with the added benefit of optional
head cell deflate; this will assist the clinician with a range of nursing
procedures including prone nursing, intubation, neck cannulation
and hygiene, while the body of the mattress continues to provide
optimal alternating pressure redistribution.
Both mattresses have been designed with specialised Vent Valves,
so that some of the cells (including the three head cells on the
Nimbus Professional mattress) can be selectively deflated to assist
with pressure area care and patient management.
The mattresses incorporate an advanced AutoMatt®sensor pad
which ensures the patient is automatically supported at optimum
pressures regardless of size, height, position or weight distribution.
Both mattresses incorporate the five Heelguard®cells at the foot
end of the mattress which ensure that the patient’s heels are
provided with the maximum pressure relief.
If cardiac arrest occurs, the mattresses can be rapidly deflated
using the CPR (Cardio-Pulmonary Resuscitation) control to allow
cardiac resuscitation procedures to be performed.
A full technical description of the Nimbus 4and Nimbus
Professional system can be found in the Service Manual, part No.
SER0007, available from Arjo.
Nimbus Pump
Front Panel
Run/Standby Button
Alarm Indicators
Tubeset
Mains Power Cable
Carry Handle (recess)
Connector
Comfort Control
Static Control Mute Control

3
Nimbus 4 Mattress
Mattress CPR and Transport Controls
Carry Handle
Securing Strap
5 Heelguard®Cells
3 Head Section Cells
8 Torso Cells 4 Thigh Cells
HEAD END
FOOT END
Drag Handle
Cable Management Flap
5 Vent Valves
CLOSED OPEN
(Constant Pressure)
Detachable Cover
CPR/Transport
Control
Transport Control
Pump Tubeset
CPR
1
3
NORMAL
TRANSPORT
2
FAST DEFLATE
CPR Control
NORMAL
TRANSPORT
Tubeset
Connector
NOTE
These controls are common to both Nimbus 4 and Nimbus Professional mattresses, and are
located at the foot end of the mattress on the opposite side to the Vent Valves.

4
Nimbus Professional Mattress
NOTE
The drag handles enable transportation of a patient in case of emergency. This is the only
situation the drag handles can be unfastened. In any other situation the drag handles must be
fastened to the base cover in order to remove the risk of tripping.
Carry Handle
Securing Strap
5 Heelguard®Cells
3 Head Section Cells 8 Torso
3 Thigh Cells
HEAD END
FOOT END
Drag Handle
Cable Management Flap
19 Vent Valves
CLOSED OPEN
(Alternating Pressure)
Shoulder Support (4th) Cell
(Alternating, No Vent Valve)
Detachable Cover
CPR/Transport
Control
Cells

5
2. Clinical Applications
Indications The Nimbus 4 and Nimbus Professional systems are indicated for
the prevention and/or management of all categories1of pressure
ulcer, when combined with an individualised, comprehensive
pressure ulcer protocol: for example, repositioning, nutritional
support, skin care. Selection should be based upon a holistic
assessment of the patient’s individual care needs.
These systems represent one aspect of a pressure ulcer
management protocol; all other aspects of care should be
considered by the prescribing clinician.
If existing wounds do not improve or the patient's condition
changes the overall therapy regimen should be reviewed by the
prescribing clinician.
The above are guidelines only and should not replace clinical
judgement.
The Nimbus 4 and Nimbus Professional mattress is designed for
patients weighing up to 250 kg (550 lb).
Contraindications Do not use Nimbus 4 and Nimbus Professional systems for
patients with unstable spinal fractures.
Cautions If patients have other unstable fractures, or conditions which may
be complicated by a soft or moving surface, advice should be
sought from an appropriate clinician before use.
While the Nimbus 4 and Nimbus Professional systems have been
designed to manage patients up to the weight limits indicated
above, those approaching this upper limit are likely to have
additional care and mobility needs and may be better suited to a
specialist bariatric system.
Active therapy (alternating) cushions may be unsuitable for
patients with poor sitting posture or pelvic deformity; advice from a
seating specialist should be sought.
Care of the patient
when sitting
Seated patients are at increased risk of pressure ulcers particularly
if they are immobile or have wounds over the seating area. For
optimal outcome, provide a pressure redistributing seat cushion in
a chair which promotes a good sitting posture and has a level base
seat to support the cushion, in addition to an individual
repositioning programme.
1. NPUAP/EPUAP International Pressure Ulcer Guideline, 2014.
NOTE
Mattress and cushion combinations may have different upper weight limits.
NOTE
Cushions should be used in combination with pressure-redistributing mattresses to provide 24-
hour therapy.

6
3. Installation
The Nimbus 4 and Nimbus Professional systems are simple to install using the following guidelines.
Preparing the
System for Use
Remove the system from the packaging. You should have the
following items:
•Nimbus pump, with integral bed bracket.
• Mains power cable (pump).
•Nimbus 4mattress replacement or Nimbus Professional
mattress replacement with covers. Do not use the
mattress without a cover.
•Tubeset.
Installing the
Mattress
1. Remove the conventional mattress from the bed frame and
check that there are no protruding bed springs or sharp
objects on the bed frame surface.
2. Unroll the mattress onto the bed base and make sure that the
CPR control is at the foot end, and the CPR label is hanging
freely.
3. Attach the mattress to the bed frame using the new fastener
straps, as shown. These eight fastener straps can be moved
to any of the 10 anchor points on the base of the mattress, to
allow for attaching the mattress to different types of bed
frame.
4. To make sure that the pressure relieving properties are not
impaired, the mattress cover must not be pulled tight and
covering sheets should fit loosely.
NOTE
Refer to Section 4, Page 10 “Controls, Alarms and Indicators” for a comprehensive description
of the controls and indicators on the pump.
NOTE
Heavily ridged bed baseboards may require special
considerations for correct system operation - consult your
Arjo sales office.
NOTE
If the bed has divided sections for independent elevation of
a patient's head and/or knees, attach the mattress to the
movable parts of the bed frame only.
NOTE
Secure drag handles by fastening them to the base cover.

7
5. Make sure that ALL the Vent Valves are closed:
6. Make sure the CPR control is closed and locked in position
and the Transport control is set to NORMAL.
Installing the Pump 1. If the pump is to be hung from the end of the bed, make sure
that the bed bracket is securely attached to the pump, and
then attach the pump and bed bracket to the bed frame.
2. Alternatively the pump can be placed underneath the bed,
either upright or lying on its back.
3. Insert one end of the mains power cable into the receptacle
on the pump.
4. Connect the other end of the mains power cable into a
suitable mains power outlet.
Cable Management In order to prevent a trip hazard, the mains power cable should be
put through one of the cable management flaps which are on each
side of the mattress base cover, as follows:
1. Locate one of the cable management flaps.
2. If necessary, open the press studs along the flap.
Closed Open
CPR
1
3
NORMAL
TRANSPORT
2
FAST DEFLATE
Transport ControlCPR Control
NORMAL
TRANSPORT

8
3. Run the mains power cable along the side of the mattress
securing the flap round the cable using the press studs.
Testing the Power
Fail Alarm
The Power Fail Alarm is powered by an internal rechargeable
battery. The duration of the alarm will depend on the level of charge
in the battery, which also depends on the age and condition of the
battery.
• The battery has a service life of between five to seven years. It
is not user replaceable and must be replaced as part of the
service procedure.
It is recommended that the alarm is tested when the pump is
installed, as follows:
1. Connect the pump to the mains power supply, and press the
Run/Standby button on the pump to put the pump in the Run
mode. Allow it to run for 10-15 seconds.
2. Remove the mains power at the wall socket without putting
the pump into Standby first.
3. The power fail alarm operates within 10 seconds, as follows:
• The yellow Alarm triangle illuminates.
• The Power indicator illuminates.
• An audible warning sounds.
4. The alarm continues until:
• The mains power is resumed.
• You press and hold the Run/Standby button to put the
pump into Standby.
5. If the alarm does not operate, run the pump for approximately
four hours to recharge the battery.
6. Retest the alarm after the battery has been recharged. Allow
the alarm to operate for approximately two minutes to ensure
that it has been adequately recharged.
Cable
Management
Flap
Press Stud
NOTE
Refer to Section 4, Page 10 “Controls, Alarms and Indicators”
for a comprehensive description of the controls and indicators
on the pump.

9
7. If the alarm does not operate for two minutes, call the service
engineer.
Connecting the
Tubeset
To connect the tubeset to the mattress and pump:
1. Locate the bottom of the tubeset connector onto the bottom of
the pump/mattress connector.
2. Pull the top of the tubeset connector up and over the top of
the pump/mattress connector, until the tubeset connector
“clicks” into position.
3. Make sure both connections are secure.
Disconnecting the
Tubeset
To disconnect the tubeset from the mattress and pump:
1. Move the tubeset connector down by pulling the tubeset
extrusion downwards, and then pull the bottom of the tubeset
connector away from the bottom of the pump/mattress
connector.
2. Lift the top of the tubeset connector from the top of the pump/
mattress connector.
System Operation The system is now ready for use. Refer to
Section 4, Page 10 “Controls, Alarms and Indicators” and
Section 5, Page 13 “Operation” for day-to-day operating
instructions.
NOTE
If the Power Fail Alarm does not operate after this test and a
service engineer has been called, the pump can continue to
be used with regular checks of the Power-On status. All
other alarms continue to function as normal.
1
2
1
2

10
4. Controls, Alarms and Indicators
Pump Controls The pump front panel has the following controls:
Run/Standby Button Press the Run/Standby button to put the pump into the Run mode;
the Run indicator will change to green.
To put the pump into Standby, press and hold the Run/Standby
button for approximately 3 seconds; this prevents accidental
operation. The Run indicator will be extinguished.
Static Mode Selects the operating mode, either Static or Dynamic. When the
pump is first powered up, its default setting is Dynamic mode. To
switch to Static mode, press and hold the Static Mode button for a
minimum of 3 seconds. Static mode is confirmed by the illumination
of the button’s yellow indicator.
To return to Dynamic mode, press and hold the button for a
minimum of 3 seconds. Dynamic mode is confirmed by the
extinguishing of the button’s yellow indicator.
Alarm Mute An Alarm Mute button is provided to silence warning sounds during
an alarm condition. Press and hold the Alarm Mute button for a
minimum of 3 seconds to mute any alarms.
Alarm Mute is confirmed by the illumination of the button’s yellow
indicator.
Nimbus
Run/Standby Mute Control
Static Mode Control
ComfortWait
High Pressure
Indicator
Low Pressure
Indicator
Power Fail
Indicator
Service
Indicator ControlIndicator
Button & Indicator
& Indicator
Pump Fault
Indicator
Alarm
Indicator
Run Mode
Indicator
NOTE
The Alarm Mute button does not operate in a Power Fail
condition.

11
Comfort Control The Nimbus 4 and Nimbus Professional systems automatically
compensate for patient weight distribution and position, to optimise
the mattress pressure relieving performance. However, the
mattress cell pressure can be manually adjusted for patient comfort
using the rotary Comfort Control.
Turn the Comfort Control clockwise for a firmer setting and
counterclockwise for a softer setting.
Pump Indicators The pump front panel has the following indicators:
Run Mode The green Run indicator below the Run/Standby button is
illuminated to confirm the pump is in Run mode.
Static Mode The yellow indicator on the Static button is illuminated when Static
mode has been selected for operation.
Alarm Mute The yellow indicator on the Mute button is illuminated when an
audible alarm has been silenced.
Wait The Wait indicator is illuminated when the mattress is being
inflated.
High Pressure The High Pressure indicator is illuminated whenever the pump
detects high pressure within the mattress.
If this condition occurs, the air supply from the pump is switched off
until normal pressure is detected. After two seconds of normal
pressure being detected the indicator is switched off and the air
supply restarted.
Low Pressure The Low Pressure indicator is illuminated whenever the pump
detects low pressure within the mattress.
This may indicate that there is insufficient pressure to support a
patient or that the Transport control is turned to the Transport
position whilst the pump is on and connected to the mattress.
The Low Pressure indicator will be switched off once normal
pressure is reached.
Alarm The pump unit incorporates a sophisticated alarm detection system
that differentiates between patient movement and genuine alarm
conditions.
Whenever an alarm condition is detected, the yellow Alarm triangle
illuminates together with an indicator of the cause of the alarm.
Additionally, an audible warning will sound, which can be
NOTE
The Alarm Mute button does not operate in a Power Fail
condition.
NOTE
The indicator will remain illuminated until the mattress has been
fully inflated.

12
temporarily silenced by pressing the Alarm Mute button for a
minimum of 3 seconds (Refer to “Alarm Mute” on page 10).
The triangular Alarm symbol is displayed with one or more of the
following indicators:
• Low Pressure (refer to “Low Pressure” on page 11).
• High Pressure (refer to “High Pressure” on page 11).
• Pump Fault (refer to “Pump Fault” on page 12).
• Power (refer to “Power Fail” on page 12).
Refer to Section 9, Page 24 “Troubleshooting and Alarm
Conditions” for possible causes of the above alarm conditions.
Pump Fault The Pump Fault indicator is illuminated when an internal pump
malfunction is detected.
The fault can only be rectified by carrying out a service on the
pump.
Power Fail The Power indicator will illuminate when a mains power failure has
been detected.
The alarm will continue until:
• The mains power is resumed, or
• You press and hold the Run/Standby button to put the pump
into Standby.
The Power Fail Alarm is powered by a rechargeable battery. The
duration of the alarm will depend on the level of charge in the
battery. The battery may have become discharged or reached the
end of its life; it is therefore recommended that the alarm is tested
before the pump is used (refer to “Testing the Power Fail Alarm” on
page 8).
Service Indicator The Service Indicator symbol will be illuminated after a set number
of running hours to indicate that the pump is ready for a service.
This service period is set to 12 months run time.
NOTE
For all alarm conditions except Power Fail, once the alarm
condition has been detected and displayed, it can only be
cancelled by pressing and holding the Run/Standby button to
put the pump into Standby.
NOTE
If the Power Fail Alarm does not operate after this test and a
service engineer has been called, the pump can continue to be
used with regular checks of the Power-On status. All other
alarms will continue to function as normal.
NOTE
The pump will continue to operate normally even when the
Service Indicator symbol is illuminated.

13
5. Operation
These instructions cover day-to-day operation of the system. Other operations, such as
maintenance and repair, should only be carried out by suitably qualified personnel.
Installing the System Before using the Nimbus 4 or Nimbus Professional system make
sure that it has been installed correctly in accordance with
Section 3, Page 6 “Installation”.
• The CPR unit on the mattress is closed and locked in position.
• The Transport control on the mattress is set to Normal.
• ALL Vent Valves on the mattress are closed.
Inflating the Mattress 1. Connect the pump to the mains power supply using the
supplied cable and press the Run/Standby button to put the
pump into the Run mode; the Run indicator will change to
green.
2. The pump runs a self test for approximately three seconds
then all the indicators on the front panel are illuminated.
3. When normal operating pressure has been reached, both the
Low Pressure and Wait lights will extinguish.
4. Place the patient on the mattress in the supine (face up)
position. Refer to Section 6, Page 18 “Nimbus Professional
Mattress: Patient Positioning Guide”.
NOTE
Refer to Section 4, Page 10 “Controls, Alarms and Indicators” for a comprehensive description
of the controls and indicators on the pump.
WARNING
DO NOT PLACE THE PATIENT ON THE MATTRESS UNTIL IT IS FULLY
INFLATED AND NORMAL OPERATING PRESSURE HAS BEEN REACHED.
NOTE
It may take up to 15 minutes to inflate the mattress.
However, at the lower end of the operating temperature
range, it may take longer to inflate. Always wait until both the
Low Pressure and Wait indicators have been extinguished.
NOTE
If the operation of the pump changes during use, refer to
Section 9, Page 24 “Troubleshooting and Alarm Conditions”
before calling a service engineer or contacting your local Arjo
sales office.

14
Comfort Control Adjust the Comfort Control to the patient’s requirements.
Operating Modes The system has two operating modes:
• Dynamic mode provides the optimum pressure relieving
performance and should be used in most cases. In Dynamic
mode the support surface beneath the patient is cycled every
10 minutes.
• Static mode provides a stable, non-moving support surface (all
cells are equally inflated).
The pump defaults to the Dynamic operating mode when first
powered up.
Select the required operating mode.
Shut Down Put the pump into Standby, by pressing and holding the Run/
Standby button for a minimum of 3 seconds; the Run indicator will
be extinguished.
• If the pump needs to be completely isolated from the mains
power supply, remove the plug from the mains power socket.
Mattress Vent Valves On the Nimbus 4and Nimbus Professional mattresses, the Vent
Valves along the side of the mattress enable individual cells to be
deflated:
1. Nimbus 4 mattress has only five Vent Valves in the
Heelguard section at the foot end of the mattress.
2. Nimbus Professional mattress:
• The three Head Section cells have Vent Valves.
• The eight Torso cells, three Thigh cells and five Heelguard
cells have Vent Valves.
• The single Shoulder Support (4th) cell has no Vent Valve
and cannot be deflated.
3. During system operation, open individual Vent Valves on the
Torso, Thigh and/or Heelguard®cells to deflate the cell and
assist with pressure area care and patient management,
including everyday interventions such as chest x-rays.
NOTE
When changing between operating modes, the patient’s
monitoring and repositioning program should be reviewed.
Foot
Head
Head
Cells
Torso Thigh
CellsCells
Heelguard
Cells
Shoulder Support Cell
Nimbus Professional Mattress - Vent Valves
End End